Multiple Sclerosis Health Center

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Side Effects of MS Treatments

Other Cautions continued...

Another oral drug is Gilenya. Before you can take this drug, you'll need to have a chickenpox vaccine if you haven't already had chickenpox. That’s because during a clinical study one person died from chickenpox while taking Gilenya. Although it isn't 100% clear that Gilenya caused the infection, "It's possible that person's ability to fight off the chickenpox virus was affected by the medication," Ratchford says. You'll also need to stay in your doctor's office to be watched for six hours the first time you get Gilenya, because it can cause a drop in heart rate after the first dose. Gilenya's most common side effects include headache, diarrhea, back pain, cough, and abnormal liver tests. The FDA says it is investigating someone in Europe who had developed PML, the brain infection mentioned above, after taking Gilenya.

Tecfidera is also an oral medication. It may cause low levels of immune cells, so your doctor will do regular blood tests to check for that. An active ingredient similar to the one in Tecfidera has been linked to four cases of PML. However, this has not been seen in patients taking Tecfidera. The four patients also had additional risk factors for PML. Tecfidera's most common side effects are flushing, stomach pain, diarrhea, nausea, and vomiting.

Working With Your Doctor to Manage Symptoms

Talking to your doctor before you start taking a new MS medication can make the potential side effects seem less frightening, and arm you with strategies to manage those side effects. "Letting them know what to expect and that it's going to improve over time goes a long way toward helping them manage those symptoms," Miller says.

It's also important to schedule regular visits to your doctor's office, especially when you start on a new drug. You'll probably see your doctor every couple of months to start, and then every six months after that, according to Ratchford.

Your doctor should give you regular blood tests to check your liver function while you are on the interferon drugs or Gilenya. People who are taking Tysabri will have to answer questions about their treatment at every monthly infusion, as part of an FDA-mandated monitoring program. Get in touch with your doctor in between scheduled visits if you see any signs of an allergic reaction (rash, swelling of the mouth), infection (fever, skin damage), or worsening of your MS.

Although you can have side effects from your MS medications, they shouldn't stop you from getting the treatment you need. Know what symptoms to watch for, get support from your doctor, and follow your treatment plan, and your MS medications should help you stay active and healthy for a long time.